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The author integrates information on the hygienic value of man-made chemical soil pollution on the population's health. He presents the results of studies of the pollution of soil and its contacting media (the sources of drinking water supply, ambient air, and crop production) with priority chemicals (heavy metals, pesticides, nitrates, nitrocompounds). The newborns and children under 14 years of age may run the greatest danger of being exposed to toxicants since all the protective systems of their organism are imperfect and are being formed.

In addition to active ingredients, the currently available pesticides comprise solvents and emulsifiers, and dispersants whose content may be as high as 85 and 30%, respectively. These components can have a substantially high effect on the toxicity and toxic kinetics of formulations, which shows a potentiating effect in many cases. From the hygienic, toxicological, and ecological points of view, it is necessary to continue studies into the combined effect of the components and active ingredients of formulations on the body and into their effect on the behavior of the latter in the environmental objects.

The paper touches upon the topical aspects of the hygiene and toxicology of fertilizers and their state sanitary-and-epidemiological examination at the present stage. It also considers guidelines for the toxicological-and-hygienic evaluation when state trials are carried out.

The paper considers the topical aspects of safe agricultural use of fertilizers. Temporary hygienic standards for the fertilizer levels of toxic elements have been developed: 8 mg/kg for cadmium; 15 mg/kg for lead; 10 mg/kg for arsenic.

The environmental and hygienic value of detergents--surfactants in the occurrence of emergencies is largely determined by their physicochemical properties and their effect on the self-purifying capacity of soil, water reservoirs, and the behavior of man-made pollutants in the environmental objects. The critical levels of anionic surfactants have been established.

The paper deals with the topical problem in the combined effect of detergents and priority pollutants (pesticides, mineral fertilizers, and heavy pollutants) on the body and the quality of the environment. Under combined man-made environmental pollution, surfactants may substantially alter the behavior and toxicity of many chemical substances, which requires that these studies should be continued.

The paper deals with modes of detection of soil cadmium, with the effects of its pollution and with toxicity on man, microorganisms and soil biocenoses. It shows why cadmium migrates and translocates into plants. The problem of development of hygienic specifications of the metal is analyzed in relation to the protective properties of soil and the data obtained from the monitoring of a region.

Heavy metals are chief contaminants of the environment, having an adverse effect on the population, especially on children. Results of hygienic and clinical observations suggest to us that compounds of heavy metals might cause changes in functions of metabolism and structure of some organs and systems raising the level of morbidity. It is necessary that a common system be set up of investigations, based on achievements of hygienic science both in this country and abroad; comprehensive investigations designed to study effects of heavy metals on human health be conducted; methodological approaches to the assessment of complex studies be worked out.

Disorders in microbiocenosis and biological activity of different types of soil were studied in a laboratory model experiment and the survival of reference and pathogenic microorganisms exposed to sulfonol and lead was evaluated. The most sensitive tests for such studies are evaluation of the number of nitrifiable bacteria, nitrifying, proteolytical, dehydrogenase, and cellulase activities, and survival of Salmonella and lactose-positive Escherichia coli in soil.

Detergents, lead, and nitrogen fertilizers were tested for their effects on the level of sugar in the beets and that of starch in the potatoes. Models were developed for estimating the quality of potatoes and beets grown under irrigation and soil nitrogen fertilization. Lead made the greatest contribution to the lowering sugar in the beets and starch in the potatoes.

Some aspects are studied of migration of the complex of priority soil contaminants anionic detergents, hexachlorocyclohexane (HCCH) and nitrogenous fertilizers. The anionic surface-active substance [symbol: see text] favours migratory properties of nitrates, HCCH. Permissible load of anionic surface-active substances on the black earth soil that comes up to 17 kg/ha is validated.

A toxicological and hygienic characterization is submitted of novel synthetic organic flocculant AEC-5, AEC-7, AEC-10 which are low-toxicity substances and are classified under the fourth class of hazards. They have no skin-resorptive, locally irritative action and are endowed with a weak cumulative activity of functional character. The AEC-5 flocculant exerts a moderately manifest sensitizing effect in the dermal route of entry.

Permissible concentrations of anionic surfactants for the soil of irrigated agricultural fields are experimentally grounded: these are as follows: 12 and 17 kg/ha (5 and 7 mg/kg) for sod-podzolic soils and black earths, respectively. By calculation, approximate permissible concentrations were also determined for other soils: 7 kg/ha (3 mg/kg) for sandy soils, 20 kg/ha (8 mg/kg) for loamy soils, and 25 kg/ha (10 mg/kg) for clay soils.

Small rivers and soils in the North Ukraine were found to be polluted by anionic surfactants. The use of surfactant-based detergents makes the population complain of poorer health. Most of them mention the irritating effects of the detergents on the skin (65 and 30% in the urban and rural areas, respectively), upper airway (54 and 48%) and allergic reactions.

Anionic surfactants (AS) not only can move from the soil to cereals, but can increase the translocation of some toxic agents (lead, copper, zinc). The tolerable anionic AS in the irrigation of soddy podzolic soils is 12 kg/ha.

Sewage irrigation of farming lands can affect the translocation of heavy metals from soil to plants. Metal mobility is likely to be due to the increased content of toxic substances and surfactants in the sewage. Therefore, it is necessary to modify an approach to growing cereals in the farming lands irrigated by sewage, by reducing the unfavourable effects on the environment and public health.

The maximum allowable dose of synthetic anionic surfactants of 12 kg/ha was recommended for irrigation of agricultural lands by sewage.

Deterioration of the quality of surface waters has a negative impact on the quality of drinking water. Hence, mathematical prediction of anthropogenic contamination of water bodies, the main sources of drinking water, is a pressing task. Mathematical models have been created for predicting the content of the priority chemical compounds, namely, surfactants, heavy metals, oil products, in the Dnieper river and its basin.

The Azotobacter agilis [correction of azobacter agile] culture appeared to be the most sensitive one among the studied test objects. Buckwheat as a test plant can be recommended in studying the toxicity of surface-active substances.

Anionic surfactant PO-ID at the level of 10, 25 and 50 kg/ha did not depress biological activity of soil and stimulated nitrogen metabolism. Water-migration and translocation indexes of this surfactant should be studied.

River Dnieper is polluted by anionic surfaceactive substances, oil, zink , copper, and mercury. Therefore the study of combined effect of these substances is nessesery.

Results of determination of surface-active substances (SAS) in the soil and water from 30-km Chernobyl zone are presented. The data evidence degrees of soil pollution with anionic SAS which may influence migration and translocations of radionuclides, salts of heavy metals and other compounds. There were found bottom deposits of anionic detergents in the river of Prypyat as well as pollution of well water in a number of villages.

Alteration of the microbial coenosis and biological activity of different types of soils as well as peculiarities of survival of sanitary-significant and pathogenic microorganisms under the effect of sulphonol and a sulphonol-lead complex have been studied in the laboratory model experiment. The most sensitive tests were as follows: the number of nitrifying bacteria; nitrifying, proteolytic, dehydrogenase and cellulase activity; survival of salmonella and lactose-positive colibacilli. Under the effect of the tested sulphonol (0.5 and 3 mg/l) and lead (0.1 and 2 mg/l) concentrations the self-purification processes in soil were not substantially disturbed, though surfactants negatively affected viability of enterobacteria.

A study of dining enterprises and laundry shift-workers of the 30-km Chernobyl accident zone revealed that surface-active substances extensively used in the zone produced a negative effect on the body (irritation of the upper respiratory tract, skin, allergic reactions). Prophylactic measures and treatment of this category of workers are discussed.

It was established that combined peroral effect of sulfonol, lead and nitrates at maximum permissible level produces more pronounced changes in the liver of white rats than when these agents are used separately. Addition of nitrates to sulfonol and lead has a tendency to potentiate the reaction of the body.

Use of surface-active substances (SAS) in the oil-extracting regions of the Ukraine should consider the fact that this is a rather small territory, densely populated, with environmental water and soil problems, significant contamination of several areas by pesticides, mineral fertilizers and complicated by the Chernobyl accidents sequels. SAS may influence the ecological-hygienic balance of the environment, they may enhance migration of many ingredients, increase their toxicity. The authors propose several measures aimed at improving the quality of preventive and actual state inspection over the oil enterprises.

The authors suggest two stages of ecological and hygienic evaluation of surface active substances widely used in oil extraction. Stage 1. Toxicological-hygienic evaluation of these substances. Stage 2. Ecological-hygienic aspects of surface active substances (migration into soil, phytotoxicity, effect on the water quality and oth.). It was established at stage 1 that proxanol, proxamin, diproxamin are compounds of minor hazard (class 4 hazard). These substances belong to local skin-irritating substances. Proxanol produces skin-resorptive effects which is confirmed by clinical signs of intoxication, reduction of weight of the experimental animals.

Chemical pollution of water reservoirs and rivers in Ukrainian SSR was noted. Anthropogenic soil pollution is also discussed, and sanitary measures for reservoirs and soil protection suggested.

Urgent problems of the interaction of surface-active substances (SAS) with other ingredients under the conditions of chemical soil pollution are discussed, in particular, under the conditions of irrigation of agricultural fields with treated municipal sewage containing detergents. Before the beginning of the irrigation season the content of anion SAS in the arable layer of the soil is 2.02-2.66 mg/kg. In the middle of the vegetation period the quantity of detergents is increased 3-4 times fold. The authors suppose, that SAS may influence translocation of heavy metals from soil into plants. However, this question should be studied more carefully in the conditions of field experience with various SAS concentrations in soil.

Results are discussed of research studies on hygienic evaluation of the most spread surface-active substances in the USSR Hungary. Anionic substances were shown to possess the most pronounced skin-irritating effect while amphoteric substances were shown to possess the most pronounced skin-irritating effect while amphoteric substances produced the least effect. For efficient joint studies the Soviet and Hungarian methods should be unified.